Chapter 15 Plant Science

bulbs

new bulbs form beside the originally planted bulb. Separate these bulb clumps every three to five years for largest blooms to increase bulb population. The clump can be dug after the leaves have withered. Bulbs are then gently pulled apart and replanted immediately so that their roots can begin to develop. Small new bulbs may not flower for two or three years, but large ones should bloom the first year. This works for the tulip and narcissus

stem cuttings

numerous plant species are propagated by stem cuttings. Some can be taken at any time of the year, but stem cuttings of many woody plants must be taken in the fall or in the dormant season

Corms

a large new corm forms on top of the old corm, and tiny cormels form around the large corm. After the leaves wither, the corms are dug and allowed to dry in indirect sunlight for two or three weeks. Then the cormels are removed and the new corms are separated from the old corms.

Whip or Tongue Grafting

often used for material one quarter to one half inch diameter. The scion and rootstock are usually of the same diameter, but the scion may be narrower than the stock. This strong graft heals quickly and provides excellent cambial contact

Cleft Grafting

often used to change the cultivar or top growth of a shoot or a young tree (seedling). It is especially successful if done in early spring

cuttings

pieces of stems, leaves, or roots for use in asexual plant propagation (shrubs/house plants)

Division

plants like daylilies, mums, and daffodils form clumps of plants. They may be dug up and cut apart to form new plants

offsets

plants w/ a rosetted stem often reproduce by forming new shoots at their base or in leaf axils. New shoots can be severed from the parents plant after they have developed their won root system. Unrooted offsets of some species may be removed and placed in a rooting medium. Some of these must be cut off, whereas others may be simply lifted off of the parent stem (date pal, haworthia, bromeliads, and many cacti

Patch Budding

plants w/ thick back should be patch budded. Done while the plants are actively growing so that their bark slips easily

Layering

a portion of an attached shoot is partially buried underground where roots develop. The new plants may then be separated from the parent plant. (figs, raspberries, blackberries, many ornamentals)

Grafting

a shoot or scion is removed from the desired plant and placed on another plant (the stock) (fruit/nut trees)

Bark Grafting

unlike most grafting methods, bark grafting can be used o large limbs, although these are often infected before the wound can heal

Leaf cuttings

used almost exclusively for a few indoor plants. Leaves of most plants will either produce a few roots but no plant, or just decay

Air Layering

used to propagate some indoor plants with thick stems or to rejuvinate them when they become leggy. The stem is slit just below a node. Then the slit is pried own with a tooth pick andthe wound is surrounded with wet unmilled spaghnum moss and tied in place. When roots pervade the moss, the plant is cut off below the root ball. Air layering works for dumbcane and rubbertree

Separation

applied to a form of propagation by which plants that produce bulbs or corms multiply

Plantlets

at the tips of runners may be rooted while still attached to the parent, or detached and placed in a rooting medium (strawberry or spider plant)

medial cuttings

first cut is made just above a node, and the second cut just above the node two to six inches down the stem. Must be positions right side up. Axial buds are always above leaves

Split Vein

for a split vein cutting, a leaf from the stock plant is detached, and its veins are slit on the lower leaf surface. the cutting is laid lower side down on the medium. New plants will form at each cut

Leaf sections

frequently used with snake plant and fibrous-rooted begonias. Begonia leaves are cut into wedges with at least one vein. A new plant will arise at the vein. Snake plant leaves are cut into two-inch sections. Roots will form fairly soon and eventually, a new plant will appear at the case of the cutting. These and other succulent cuttings will root if kept too moist

tip cuttings

made by detaching a two-to-six- inch piece of stem, including the terminal bud. the cut is made just below a node. Lower leaves that would touch or be below the medium are removed before dipping in the rooting medium and placed in the media. At least one node must be below the surface

Stolons

Strawberries produce stems that grow horizontally along the soil surface. New plants are produced at joints along the stolons

Cane Cuttings

stems are canelike and cuttings are cut into sections that have one or two eyes, or nodes

Rhizomes

Iris, Bermuda grass, Johnsongrass and other plants produce underground stems called rhizomes. The rhizomes can be dug, cut into sections, and the sections planted. New plants and roots grow from joints on the rhizomes

Whole Leaf without petiole

This is used for plants with sessile or petioless leaves. The cutting is inserted vertically into the medium. A new plant will form from the axillary bud. The leaf may be removed when the new plant has its own roots

Budding

a bud is removed from the desired plant and placed on the stock (fruit trees and roses)

Division

plants with more than one rooted crown may be divided and the crowns planted separately. If the stems are not joined, they can be gently pulled apart. If the crowns are united by horizontal stems, the stems and roots need to be cut with a sharp knife to minimize injury

Simple Layering

stem bent to the ground and partially covered with soil, leaving the last six to twelve inches exposed. The tip is bent into a vertical position and staked in place. The sharp bend will often induce rooting, but wounding the lower side of the branch or loosening the bark by twisting the stem may help. Simple layering is used with rhododendron and honeysuckle

Stolons and Runners

stolon is horizontal, fleshy stem that can root, then produce new shoots where it touches the medium. A runner is a slender stem that originates in a leaf axil and grows along the ground or downward from a hanging basket, producing a new plant at its tip

Root Cuttings

taken from two to three year old plants during their dormant season when they have a large carb supply. Root cuttings of some species produce new shoots, which then form their own root systems; root cuttings of other plants develop root systems before producing new shoots

Single Eye

the eye refers to the node. This is used for plants with alternate eaves when space or stock material are limited. The stem is cut about one-half inch above and below a node. The cuttings are placed horizontally or vertically in the medium

Whole leaf w/ petiole

the leaf and half to one half inches or petiole are detached. The lower end of the petiole goes into the medium. One or more new plants will form at the base of the petiole the leaf may be severed from the new plants when they have their own roots, and the petiole reused

Mound (stool) Layering

the plant is cut back to one inch above the ground in the dormant season. In the psring, soil is mounded over the emerging shoots to enhance their rooting

Tip Layering

the shoot tip is inserted in a hole three to four inches deep and covered with soil. The tip grows downward first, then bends sharply grows upward. Roots form at the bend and the recurved tip becomes a new plant. The tip layer plant can be removed and planted in the early spring or late fall. Tip layering can be used on purple and black raspberries, and trailing blackberries

Tillers or Suckers

these are formed at the base of some trees like mimosa, sassafrass, and some plums when cut. Blackberries, rabbit eye blueberries, raspberries and many grasses also produce tillers. These tillers may be cut free from the main plant to form new plants

Chip Budding

this budding method can be used when the bark is not slipping. Slice downward into the rootstock at a forty-five-degree angle through one-quarter of the wood

T-Budding

this is the most commonly used budding technique. It is made when the bark is slipping

Double Eye

this is used for plants with opposite leaves when space or stock material is limited. Stems are cut about on half inch above and below the same node and inserted into the medium vertically with the node just touching the surface

Heel Cutting

this method uses stock material with woody stems efficiently. Make a shield shaped cut about halfway through the wood around a leaf and axial bud, the shield in inserted horizontally into the medium

Compound layering

this method works for plants with flexible stems. The stem is bent to the rooting medium as for the simple layering, but stem sections are alternately covered and exposed. The lower side of the stem sections to be covered is wounded. Compound layering works for heart leaf philodendron and pothos